Question

i need the answer asap plz A child rides her bike at a rate of 12.0 km/hr down the street. A squirrel suddenly runs in front of her so she applies the brakes and slows to 8.0 km/hr in 0.25 sec. What is the acceleration of the bike rider during this period? 1.0 km/hr/sec -1.0 km/hr/sec 16 km/hr/sec -16 km/hr/sec

Answer 1

-16 km/hr/sec because she slows down 4 km/hr (12 - 8) in 0.25 seconds. in one second (0.25 sec * 4) she would slow down by 16 km/hr (4 * 4). it’s negative acceleration because she’s slowing down

Answer 2

Answer:      Acceleration of the bike rider during this period is   -16 km/hr/s

Explanation:Average acceleration is equal to change in velocity divided by time taken

therefore, a=\frac{Vf-Vi}{t}

=> $a=\frac{8-12}{0.25} km/hr/s = -16 km/hr/s$